SGI gooses InfiniteStorage arrays with new NetApp controllers

Supercomputer and high-density server maker Silicon Graphics shipped over 600PB of disk capacity last year across its InfiniteStorage product line, and it is revving up its entry InfiniteStorage 5000 series to get a bigger bite of storage attachments for HPC and big data workloads that want cheap, fat, and fast disk arrays.

SGI is not rich enough to make its own storage controllers for block storage devices. Instead, the company partners with NetApp for its Engenio line of controllers (which NetApp bought from LSI Logic in March 2011) for the IS5000 Series of entry products, and has cut a similar OEM deal with DataDirect Networks for its SFA line, which it rebrands as the IS15000, IS16000, and IS17000.

The new IS5600 arrays are based on a beefed up Engenio controller based on a custom ASIC, not an x86 processor, Floyd Christofferson, director of storage product marketing at SGI, tells El Reg.

The IS5600 is a next-generation RAID platform and handles both hard disks and solid state disks, the latter of which come is SAS and nearline SAS variants. The IS5000 controller from NetApp was able to scale to 192 drives for a max of 576TB and is the entry system, while the controller in the IS5500 was able to host 384 drives and a maximum of 1.2PB. The IS5600 controller has the same drive count and capacity scalability, but Christofferson says that it delivers about 2.5 times the I/O performance out of the controller.

Three different IS5600 enclosures

The IS5600 is based on the existing SGI disk/SSD enclosures, which include:

A 12-bay unit that is 2U high and that houses a dozen NL-SAS and SSD drives in 3.5-inch form factors.

A 24-bay unit that is 2U high and that holds two dozen SAS and SSD drives in 2.5-inch form factors.

A 60-bay unit that is 4U high, which has five disk trays that slide out as a unit that have a dozen 3.5-inch SAS, NL-SAS, or SSD drives each.

All of these enclosures are front loading, and the 60-bay unit allows you to slide out a tray and service a drive without taking the tray or any other part of the enclosure offline.

When you add it all up says Christofferson, the IS5600 arrays have a 35 per cent smaller footprint and about 50 percent lower cooling costs compared to an equivalent amount of I/O performance and capacity in the IS5500 arrays. And as you can see from the table below, the new NetApp Engenio controller has a slightly higher burst I/O rate but more importantly considerably more burst and sustained I/O bandwidth rates for reads and writes.

The IS5600 only offers SAS links to hosts, while the IS5000 offered Fibre Channel, SAS, or iSCSI links and the IS5500 added InfiniBand to the base Fibre Channel support with iSCSI and SAS optional.

How the IS5600 stacks up against the IS5500

The IS5600 includes a new rev of NetApp's SANtricity controller code, which SGI rebrands as InfiniteStorage System Manager 10.86. The key new feature in this software update is something called Dynamic Disk Pools, which is an improvement over RAID 6 data protection.

With DDP, an array failed drive can achieve something on the order of 85 to 90 per cent of its normal performance in this degraded state, which is better than the 60 to 70 per cent performance you see in a RAID 6 implementation.

DDP spreads data, parity, and spare drive capacity over a pool of disks rather than locating all of the spare capacity in a single physical drive. By doing this, you can rebalance a pool of parity a minimum of twice as fast as it takes to rebuild a drive in a RAID 6 config.

The IS5600 arrays will be available in April. Pricing was not announced, but SGI plans to run the IS5600 with 36TB of raw capacity through the SPC-2 benchmark tests, and that machine loaded up cost $228,000. That machine will have 2.5 times the capacity per spindle compared to Oracle, IBM, and Fujitsu arrays in the same class. ®